stupid simple over drive

[pinkjimiphoton]

look ma, no knobs... it thinks its a fuzz. try it. cleans up great, nice ampish overdrive.

which circuit did i reinvent this time??

whole thing is built on the back of an ic socket.... sounds a lot like the liberal komrade boost...not too shabby

[pinkjimiphoton]

[booj]

And there you have it

[mth5044]

Sounds awesome! Thanks for sharing. Have to find something to use the other opamp fer.

Is it still not useable for commercial use if spelled wrong? 

[samhay]

Cool - I like the fact that it looks like you could swallow it before you go through customs if need be.

It's an op-amp with a gain of 100 into an asymmetric diode clipping arrangement.
The op-amp is inverting, so the input impedance is 10k. This might be a feature, but if you use a 5532 instead, you could use the other half to buffer the input.
The cap hanging off the bias voltage divider is usually 10u+. If you used 100p, then the bias might sag quite a bit - not sure if you can hear this, and whether it adds to the silicon mojo.

[kingswayguitar]

the back of an ic socket...? how come i never thought of that
6:00 - 6:40 is sweet
but i skipped through the video a bit. do you show the guts?

[therizky]

this looks cool... and simple. gotta try it.

[alfafalfa]

Sounds really good for such a simple design !

Did you say the resistor to ground on the input is 4.7 Meg because  it's not very legible on the drawing.
Sorry to be a nag but what about the current drawn ?  Doesn't the 5534 opamp draw quite a lot of current?
Regards,  Alf

[Gus]

http://www.montagar.com/~patj/fuzz001.gi
http://www.diystompboxes.com/pedals/lbm.gif
http://fuzzcentral.ssguitar.com/schematics/mufffuzzicschem.gif

The gain is 1meg / (10K .047uf 4.7meg plus the RLCs of the guitar or bass and cable plugged into the input)  

It can also be thought of circuit that look something like the following and other circuits The C to B resistor is like the 1meg out to - input the 10k input is like the 47K input the big difference the opamp has more openloop gain

Even the first stage of a FF, feedback resistor from Q2 E to Q1 B and then the guitar RLC and cable is where the 10K input is in your schematic

The 4.7meg looks to be an antipop resistor

EDIT
A sim idea using two transistors from reading this thread
not built
but note the way the gain is set-up and how close it is in some ways to the stupid simple overdrive

[therecordingart]

So it's an inverting Blue Clipper with asymmetrical clipping?

[pinkjimiphoton]

Sounds awesome! Thanks for sharing. Have to find something to use the other opamp fer.

Is it still not useable for commercial use if spelled wrong? 

well, you guys  can make some, and if ya don't like 'em, sell 'em. like... a couple for your friends, maybe a dozen to get the new guitar ya wanted or some eggs or something..

but corporations aren't allowed. diy'r's can tho. and if anybody thinks this thing is cool enough to do commercially, they can contact me.

it sounds horrible in the video. in the room it is much better sounding!!

i reccomend adding a volume pot. as an "only" pedal into an amp it's fine, but it's gotta bigger boost off the breadboard than on it.

10-100k standard should be fine.

Cool - I like the fact that it looks like you could swallow it before you go through customs if need be.

It's an op-amp with a gain of 100 into an asymmetric diode clipping arrangement.
The op-amp is inverting, so the input impedance is 10k. This might be a feature, but if you use a 5532 instead, you could use the other half to buffer the input.
The cap hanging off the bias voltage divider is usually 10u+. If you used 100p, then the bias might sag quite a bit - not sure if you can hear this, and whether it adds to the silicon mojo.

it was just basic experimenting with the mini breadboard mike sent me the other day... since i'm obviously OCD i had to mess with it...

my buddy doug gave me a box full of little plug in ic buffer cards... they're cool, cuz ya can wire 'em up a bunch of different ways and have preamps, buffers etc just changing a couple parts.

so that led to this, sorta... i swiped the chip out and then started seeing how many 10k resistors i could make it run with.

the cap in the power supply should be 100u, not 100p... i must have typo'd again 

but i actually used 200p on pins 3 and 4 of the chip, as it was handy. i never put the anti-pop in on this one, and found a mistake on the breadboard... i'd forgotten the 10k resistor between the chip and the output cap (caught it while i was building).

this thing doesn't sound like silicon. it sounds like germanium almost. it's really warm and clear right up to the breakup point. sounds bloody awesome into my twin, i'd like to hear it thru my bud's old ampeg!!

the back of an ic socket...? how come i never thought of that
6:00 - 6:40 is sweet
but i skipped through the video a bit. do you show the guts?

here's a crummy phone shot or two

from the side, chip down.. i had shrink wrapped all the stuff together where i could for stability, but you can see the little cap and the diode clipper. and the size of it. the input and output cap
are on either end of the chip, standing up along the sides, so even with the big .47 chicklet, it's still pretty small. then wrap the whole mess in electrical tape, and it looks almost like a home made optoisolator, maybe twice that size...



here's a pic from the top...

you can see it pretty much fits on my thumbnail

Sounds really good for such a simple design !

Did you say the resistor to ground on the input is 4.7 Meg because  it's not very legible on the drawing.
Sorry to be a nag but what about the current drawn ?  Doesn't the 5534 opamp draw quite a lot of current?
Regards,  Alf

yah, 4.7m, but i didn't use it other than on the breadboard, got no pops with it either way. it was just an arbitrary resistor, i have a bag of 100 of them ones and figured it was fine.

no idea about current draw, but it sat running on the breadboard on a battery i pulled out of my tonebender that's been in there for months... and i left it running from about 10 am when i started til about 10 pm when i did the video.

i made a little plug thing, with a barrel connector on one side and a 9v snap on the other... it's convenient for when i wanna add/subtract germanium pnp's from my rig, or if the pedal is just too small to fit a battery in, like this.

since it can't house a battery (and i'm thinking about how in hell to fit a volume knob in there... maybe a 9mm would just fit) and will run on a wart, i wasn't worried about it. but i can't imagine it drawing too much.

http://www.montagar.com/~patj/fuzz001.gi
http://www.diystompboxes.com/pedals/lbm.gif
http://fuzzcentral.ssguitar.com/schematics/mufffuzzicschem.gif

The gain is 1meg / (10K .047uf 4.7meg plus the RLCs of the guitar or bass and cable plugged into the input) 

It can also be thought of circuit that look something like the following and other circuits The C to B resistor is like the 1meg out to - input the 10k input is like the 47K input the big difference the opamp has more openloop gain

Even the first stage of a FF, feedback resistor from Q2 E to Q1 B and then the guitar RLC and cable is where the 10K input is in your schematic

The 4.7meg looks to be an antipop resistor

EDIT
A sim idea using two transistors from reading this thread
not built
but note the way the gain is set-up and how close it is in some ways to the stupid simple overdrive

yes, the 4.7m was just an antipop, not even necessary probably cuz it's all ptp inside.

it's funny, cuz i was thinking i wonder if i could make an ic fuzzface, it was kinda what i was trying to do. the input impedance makes it feel like one, interactively with the guitar, and the circuit simplicity kinda has that smooth ge sound. there's a certain *SOMETHING* ... a sweetness and warmth that's kinda tubey and brown in a good way with germanium that's not quite breaking up yet, and this takes ya right into that ball park.

the first design is cool, but the second one i REALLY like, gus... it looks like the same thing, but with transistors... and i bet it will sound ace.

i can't go near my workbench today, whole family is snowed in.... they know where i sleep, and we have a dirt basement and lime is cheap. <g>

but i'll have to breadboard it to see what's what.

i tried putting clipping in the feedback path too, but i couldn't get enough balls that way with the single chip.

thanks for the schematics of the other boxes, too... seen 'em. they're a lot more complex, i like to see just how stripped down something can be made
once in a while. this could have the input and output resistances removed and still work, tho the tone will change some.

now... obviously, i could have used a dual opamp, but then it becomes problematic, cuz i'd have to add more support passives, and at least with my chops, i'm not up to the task. with little 8th watt resistors, i bet it could be done... but also, then, it would NEED control knobs.

one of the nice things about this is it's wide open and your guitar drives it. it's really almost the same (and almost sounds the same) as the bias-less one transistor ge boost (liberal komrade boost, or lkb1) i posted a couple weeks back.

here's a rough layout for the point to point version

i forgot the 10k output resistor on these as i said before, and i built as much directly ON the socket as possible.. so there's actually 2 resistors crossed beneath the 100u cap on the one i built.



note my note to myself to revise it. dumbass.

here's a vero layout



and here's a very cheezy pcb/perf/schematic layout




glad you guys diggit. i tried this thing with a jfet and a normal transistor for a front end, too, and it just wasn't the same.. tho some combinations of parallel yielded some really cool broken jagged fuzz.

have fun!

[pinkjimiphoton]

So it's an inverting Blue Clipper with asymmetrical clipping?

beats me. i'd have to look at a blue clipper.




not really. different values and biasing, more parts. i mean, yes, it has a 10k resistor in the output, and a .047u on the input, but other than that, no, not that i see.
even a 4558 sounds different in the way it clips.

so nope. i don't think it's a blue clipper. yes, it does have asym clipping (which can also be omitted for more of a straight overdrive, it still distorts but is smoother with the diodes)

so... it ain't a blue clipper... what else could it be?  i mean, face it, it's a goddamn opamp with a diode clipper, it ain't rocket science.

[Gus]

Mark Hammer Gruntbox thread
http://www.diystompboxes.com/smfforum/index.php?topic=35675.20   reply 32

Jimi your circuit is most like the "Simple Clipper" from 2007
http://www.diystompboxes.com/smfforum/index.php?topic=59426.0  reply4 and reply 6 reply 10 schematic reply 20 read all my replies I posted some good things

This is an inverting opamp amp circuit.  If it was driven by a perfect voltage source(0 ohms) it would have a gain of 100k/10K or a 100 as posted before
HOWEVER and this is a BIG HOWEVER
when a passive guitar or bass with their RLCs from the resistors(potentiometers), pickup resistance and capacitance and inductance, tone cap(s) and cable capacitance this adds to the input 10K

so the gain is more like 100k/ (10K + the guitar RLC and cable)

The opamp "wants" the - input to be the same as the + input(1/2 power supply) so when  a signal is applied to the - input the output moves to drive the - back to 1/2 the power supply voltage
Now using OHMS law
what current is needed and the output voltage swing depends on the feedback resistor value and input resistor value and signal.  The larger the output to - input value resistor will need more output voltage  swing to drive the same current to the - input
The input node "wants" to be 0 ohms
I=E/R current= voltage / resistance

Look at bottom left Jimi does not have a  CC cap note where the curve crosses at a gain of 100 Page 6 http://www.ti.com/lit/ds/symlink/ne5534.pdf

The blue clipper and other circuits  like it don't have the same input interaction with a passive guitar or passive bass

[samhay]

^so the gain is more like 100k/ (10K + the guitar RLC and cable)

Quite right - so Jimi. Does it sound different if you put a buffer in front of it?

[Gus]

samhay

Have you seen this thread? http://www.diystompboxes.com/smfforum/index.php?topic=105324.0

[pinkjimiphoton]

^so the gain is more like 100k/ (10K + the guitar RLC and cable)

Quite right - so Jimi. Does it sound different if you put a buffer in front of it?

you lose the interaction between the circuit and the guitar with a buffer or gain stage in front of it... the tone stays the same... no matter where you set your guitar level at witht he buffer, it keeps more of a drive sound and was imho way too bright.

[pinkjimiphoton]

Mark Hammer Gruntbox thread
http://www.diystompboxes.com/smfforum/index.php?topic=35675.20   reply 32

Jimi your circuit is most like the "Simple Clipper" from 2007
http://www.diystompboxes.com/smfforum/index.php?topic=59426.0  reply4 and reply 6 reply 10 schematic reply 20 read all my replies I posted some good things

This is an inverting opamp amp circuit.  If it was driven by a perfect voltage source(0 ohms) it would have a gain of 100k/10K or a 100 as posted before
HOWEVER and this is a BIG HOWEVER
when a passive guitar or bass with their RLCs from the resistors(potentiometers), pickup resistance and capacitance and inductance, tone cap(s) and cable capacitance this adds to the input 10K

so the gain is more like 100k/ (10K + the guitar RLC and cable)

The opamp "wants" the - input to be the same as the + input(1/2 power supply) so when  a signal is applied to the - input the output moves to drive the - back to 1/2 the power supply voltage
Now using OHMS law
what current is needed and the output voltage swing depends on the feedback resistor value and input resistor value and signal.  The larger the output to - input value resistor will need more output voltage  swing to drive the same current to the - input
The input node "wants" to be 0 ohms
I=E/R current= voltage / resistance

Look at bottom left Jimi does not have a  CC cap note where the curve crosses at a gain of 100 Page 6 http://www.ti.com/lit/ds/symlink/ne5534.pdf

The blue clipper and other circuits  like it don't have the same input interaction with a passive guitar or passive bass

thanks gus, i think i'm starting to "get it" a little more.

yes, the simple clipper is close, but still different in the voicing and biasing. i finally made something (slightly) unique. barely, even.

sp...it's doing almost the same thing as the other booster... neat. it's an interesting, and to my ears, useful sound.

[Gus]

Jimi

You might want to try a 741 because of its different open loop gain curve compared to a 5534

Look up a 741 and note what the frequency is when the gain set at 100 crosses the curve then do the same with a 5534

[pinkjimiphoton]

i still have the original set up on the board gus, i will tr\y that and a couple other old metal cap ic's i have and report back. i will look at the links, thanks bro...
probably way above my paygrade.

[pinkjimiphoton]

gut shot



gonna try and squeeze a 9mm volume pot under the shaft of the output plug... just enough room.